Amniocentesis: Answers to the Most Commonly Asked Questions
Yes, an amniocentesis comes with some risks, though in general, the chance that you'll develop serious complications is quite low. Here are some of the possible complications:
- Loss of amniotic fluid: You may experience a leakage of amniotic fluid after this procedure. Most of the time, the leakage is minor, stops on its own within a week, and doesn't cause any problems.
You can expect your amniotic fluid levels to return to normal in about three weeks. However, in rare situations, the leakage may continue, which can increase the risk for other problems, such as premature delivery, deformed bones, and incomplete lung development. If you have ongoing leakage of amniotic fluid, your healthcare provider will monitor you and your fetus closely to help prevent further complications.
- Fetal injury: There have been reports of fetuses being injured by the needle during an amniocentesis. Some of the reported injuries have resulted in blood loss, eye injury, and bowel problems. However, it is not clear that these injuries were actually caused by the amniocentesis.
Using ultrasound to guide the needle greatly reduces the chance that the needle will come in contact with the fetus and cause injury. In fact, one large study that looked at over 2,000 pregnancies during which an ultrasound was used to guide an amniocentesis did not find any instances of fetal injury.
- Fetal malformations: There may be a slightly increased risk for problems in the developing baby after an amniocentesis. These problems include club foot, hip dislocation, and lung problems, and they may be related to the loss of amniotic fluid. Not all studies have shown an increased risk, though, so it's difficult to know for certain how real the risk is. If there is a risk, it is likely very low. If you have concerns, talk to your healthcare provider.
- Infection: There is a small chance that women with certain chronic infections, like hepatitis or HIV, could pass the infection to their developing baby during an amniocentesis.
- Miscarriage: One of the risks many women worry about with an amniocentesis is the risk for miscarriage. Fortunately, this risk is very low. The ACOG estimates that 1 in 300 to 500 women will have a miscarriage from an amniocentesis -- that's only 0.2 to 0.3 percent. Still, it's a risk that you might be unwilling to take.